Folding Knots Using a Team of Aerial Robots

TL;DR

This paper introduces a novel aerial robot team method for folding knots midair, leveraging a new knot representation and trajectory planning to achieve real-time, efficient knot manipulation in simulation.

Contribution

It proposes a new aerial robot approach for knot folding using a simplified cable model and a leader-follower trajectory design, enabling real-time execution.

Findings

Method successfully folds various knots in simulation.

Approach is computationally efficient for real-time application.

New knot representation simplifies complex cable configurations.

Abstract

From ancient times, humans have been using cables and ropes to tie, carry, and manipulate objects by folding knots. However, automating knot folding is challenging because it requires dexterity to move a cable over and under itself. In this paper, we propose a method to fold knots in midair using a team of aerial vehicles. We take advantage of the fact that vehicles are able to fly in between cable segments without any re-grasping. So the team grasps the cable from the floor, and releases it once the knot is folded. Based on a composition of catenary curves, we simplify the complexity of dealing with an infinite-dimensional configuration space of the cable, and formally propose a new knot representation. Such representation allows us to design a trajectory that can be used to fold knots using a leader-follower approach. We show that our method works for different types of knots in simulations. Additionally, we show that our solution is also computationally efficient and can be executed in real-time.